libsasl Cleanup

This step releases all the resources in the SASL library and the
plug-ins. The client and server call sasl_done() to release libsasl() resources and to unload all the SASL plug-ins. sasl_done() does not release SASL connection contexts. Note that if an application
is both a SASL client and a SASL server, sasl_done() releases
both the SASL client and SASL server resources. You cannot release the resources
for just the client or the server.

Caution –

Libraries should not call sasl_done(). Applications
should exercise caution when calling sasl_done() to avoid
interference with any libraries that might be using libsasl.